[Amniotic band syndrome: prenatal diagnosis and management challenges (about 2 cases of lethal malformations)].

Amniotic band syndrome (ABS) comprises of a spectrum of complex congenital malformations mainly interesting the limbs, but even the craniofacial region and the thoracoabdominal axis. There are two major opposing pathophysiological theories: premature rupture of the amniotic sac (exogenous growth theory) would result in the formation of fibrous bands which would lead to strangulation, thus causing the observed abnormalities; the endogenous theory holds that this is a syndrome of vascular origin and that the bands have no causative role. Prognosis depends on the severity of malformations.